Growers in the horticultural industry face a daily need for efficient and economical methods of production. The slightest competitive edge can mean the difference in maintaining the status quo of a business in relation to other businesses as well as allow the business to grow.
Currently seed crops are grown in a cell tray or flat to be later transplanted into a finished container such as a three inch, or four inch diameter pot. The reason for germinating in a cell or flat versus a finished container is the expensive production area a crop would require for an unreasonable length of time.
The process of getting a seed to a marketable product is a labor intense undertaking. First cell trays/flats must be filled with soil, then sown with seed, then covered with additional soil or vermiculite, and then watered. The individual trays are then placed in an environment conducive for germination and later transported to a greenhouse for additional light and growth. The trays are again moved to beds ready to accept small plants. Workers then transplant the product to the finished pot size. Finally, the pots are manually separated from one another so the seedlings can continue to grow several weeks prior to shipments to nurseries, retail stores and the like.
In horticulture, as with any industry reduction of manual tasks with automation and more efficient handling is a must to production of any type. Secondly, and most importantly is space usage.
Greenhouses require an exorbitant amount of energy for both heating and cooling. The trend today has been moving toward larger greenhouses with high ceilings of some fifteen feet or more. Maintaining moderate temperatures year-round has made space utilization in these greenhouses an important financial concern.
Stackable trays have been proposed in the nursery industry where each tray has insertion areas for planting pots to be adjacent to one another. See U.S. Pat. No. 3,549,018 to Wilson; U.S. Pat. No. 3,825,126 to Pohl et al.; U.S. Pat. No. 4,118,892 to Nakamura et al.; U.S. Pat. No. 4,242,834 to Olsen; U.S. Pat. No. 4,251,951 to Heinstedt; U.S. Pat. No. 4,684,013 to Jacobs; and U.S. Pat. No. 4,878,313 to Polestel. However, there are many problems with these types of stackable trays.
For example, each of these patents require the trays to be generally injection molded from plastic. The molds needed to create these trays can be inherently expensive. Furthermore, the plastic material may fatigue and crack if several trays or more are stacked on top of one another. Furthermore, the trays in these patents when stacked do not allow for sufficient air space and light penetration between the trays to allow seedlings in the pots to grow. The close compressing of each these stacked trays to one another further promotes disease to transfer from one tray to another since disease is often carried by water. Water coming from one tray would inherently pass to a lower tray and so forth. These trays are stacked for storage purposes only. Still furthermore, these types of trays are often discarded after only one or two uses and are rarely reusable.
Wire pallets have been proposed in the prior art. See U.S. Pat. No. 3,701,326 to Herman and U.S. Pat. No. 3,756,167 to Wilson. However, neither of these patents allow for pots to be separately secured on the pallets. Still furthermore, there is no structure in these patents for allowing the pallets to be stacked on top of one another while maintaining an airspace between the pallets.